<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        /* backgroud-color:#aaa; */
        /* padding区域是有背景颜色的 */
        div.box{
            width: 200px;
            height: 200px;
            padding:15px;
            border: 1px solid #000;
            background-color: aqua;
        }
    </style>
</head>
<body>
    <div class="box">
        padding区域是有背景颜色的
    </div>
</body>
</html>